Binding the visibility of WPF elements to a property

How to set the visibility of your WPF user interface item so that it may be hidden/collapsed or shown as desired Step 1: Create a new WPF Application visibilitybinding1 Step 2: Modify the MainWindow.xaml to create a User control Let's keep it simple - a button: [code language="xml"] <Window x:Class="VisbilityBinding.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:local="clr-namespace:VisbilityBinding" mc:Ignorable="d" Title="MainWindow" Height="350" Width="525"> <Grid> <Button Width="100" Height="30" Content="OK!" /> </Grid> </Window> [/code] Step 3: Create the ViewModel classes This is primarily to implement the INotifyPropertyChanged members BaseViewModel.cs [code language="csharp"] using System; using System.ComponentModel; using System.Diagnostics; namespace VisibilityBinding { public abstract class BaseViewModel : INotifyPropertyChanged { #region INotifyPropertyChanged Members public event PropertyChangedEventHandler PropertyChanged; #endregion protected void OnPropertyChanged(string propertyName) { VerifyPropertyName(propertyName); PropertyChangedEventHandler handler = PropertyChanged; if (handler != null) { handler(this, new PropertyChangedEventArgs(propertyName)); } } [Conditional("DEBUG")] private void VerifyPropertyName(string propertyName) { if (TypeDescriptor.GetProperties(this)[propertyName] == null) throw new ArgumentNullException(GetType().Name + " does not contain property: " + propertyName); } } } [/code] MainWindowViewModel.cs [code language="csharp"] namespace VisibilityBinding { public class MainWindowViewModel : BaseViewModel { private bool _hasInstalled; public MainWindowViewModel() { HasInstalled = false; } public bool HasInstalled { get { return _hasInstalled; } private set { _hasInstalled = value; OnPropertyChanged("HasInstalled"); } } } } [/code] Step 4: Update the MainWindow.xaml to bind to this visibility property Nexct up is to update the MainWindow.xaml by including the DataContext, Visibility converter etc: [code language="xml"] <Window x:Class="BindingVisibility.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:local="clr-namespace:BindingVisibility" mc:Ignorable="d" Title="MainWindow" Height="350" Width="525" d:DataContext="{d:DesignInstance Type=local:MainWindowViewModel, IsDesignTimeCreatable=True}"> <Window.DataContext> <local:MainWindowViewModel/> </Window.DataContext> <Window.Resources > <BooleanToVisibilityConverter x:Key="BoolToVisibilityConverter" /> </Window.Resources> <Grid> <Button Visibility="{Binding HasInstalled, Converter={StaticResource BoolToVisibilityConverter}}" Width="100" Height="30" Content="OK!" /> </Grid> </Window> [/code] Step 5: Try it! So that when switch HasInstalled = false the OK button disappears: visibilitybinding2 And by reinstating HasInstalled = true the OK button is visible again: visibilitybinding1

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